adeelarshad82 writes: Granted that iPhone 3G is about 3 years old but some of us who still have it are tempted to update it to iOS 4 for the folders, threaded e-mail and iBooks even if it means jail-breaking the phone. Unfortunately though, as it turns out, it's really not worth the hassle. Not only does the update slow the phone, in some cases by a fraction of a second and in others much more, but it's a nightmare to downgrade back to iOS 3.